U.S. patent number 7,720,532 [Application Number 10/558,831] was granted by the patent office on 2010-05-18 for clean margin assessment tool.
This patent grant is currently assigned to Dune Medical Ltd.. Invention is credited to Gil Cohen, Iddo Geltner, Dan Hashimshony.
United States Patent |
7,720,532 |
Hashimshony , et
al. |
May 18, 2010 |
Clean margin assessment tool
Abstract
An integrated tool is provided, having a tissue-type sensor, for
determining the tissue type at a near zone volume of a tissue
surface, and a distance-measuring sensor, for determining the
distance to an interface with another tissue type, for (i)
confirming an existence of a clean margin of healthy tissue around
a malignant tumor, which is being removed, and (ii) determining the
depth of the clean margin. The integrated tool may further include
a position tracking device and an incision instrument. The soft
tissue may be held within a fixed frame, while the tumor is being
removed. Additionally a method for malignant tumor removal is
provided, comprising, fixing the soft tissue within a frame,
performing imaging with the hand-held, integrated tool, from a
plurality of locations and orientations around the soft tissue,
reconstructing a three-dimensional image of the soft tissue and the
tumor within, defining a desired clean margin on the reconstructed
image, calculating a recommended incision path, displaying the
recommended path on the reconstructed image, and cutting the tissue
while determining its type, at the near zone volume of the incision
surface. The method may further include continuously imaging with
the cutting, continuously correcting the reconstructed image and
the recommended incision path, and continuously determining the
tissue type, at the near zone volume of the incision surface.
Inventors: |
Hashimshony; Dan (Givat Ada,
IL), Cohen; Gil (Jerusalem, IL), Geltner;
Iddo (Herzlia, IL) |
Assignee: |
Dune Medical Ltd. (Caesaria,
IL)
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Family
ID: |
34994122 |
Appl.
No.: |
10/558,831 |
Filed: |
March 23, 2005 |
PCT
Filed: |
March 23, 2005 |
PCT No.: |
PCT/IL2005/000330 |
371(c)(1),(2),(4) Date: |
November 29, 2005 |
PCT
Pub. No.: |
WO2005/089065 |
PCT
Pub. Date: |
September 29, 2005 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20060253107 A1 |
Nov 9, 2006 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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60555901 |
Mar 23, 2004 |
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Current U.S.
Class: |
600/547; 606/1;
600/587; 600/439 |
Current CPC
Class: |
A61B
18/082 (20130101); A61B 5/4312 (20130101); A61B
5/0084 (20130101); A61B 34/20 (20160201); A61B
8/4245 (20130101); A61B 5/415 (20130101); A61B
5/0091 (20130101); A61B 5/01 (20130101); A61B
5/0507 (20130101); A61B 8/0858 (20130101); A61B
5/06 (20130101); A61B 5/053 (20130101); A61B
2090/378 (20160201); A61B 5/0071 (20130101); A61B
5/055 (20130101); A61B 2090/061 (20160201); A61B
2034/2051 (20160201); A61B 8/4472 (20130101); A61B
2017/00026 (20130101); A61B 2090/367 (20160201); A61B
5/0086 (20130101); A61B 2034/107 (20160201); A61B
8/12 (20130101); A61B 5/0075 (20130101); A61B
5/015 (20130101); A61B 2034/2055 (20160201) |
Current International
Class: |
A61B
5/05 (20060101); A61B 17/00 (20060101); A61B
5/103 (20060101); A61B 5/117 (20060101); A61B
8/00 (20060101) |
Field of
Search: |
;600/372,373,382,439,547,587 ;324/632,643 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
688 352 |
|
Mar 1998 |
|
AU |
|
3637549 |
|
May 1988 |
|
DE |
|
419235 |
|
Mar 1991 |
|
EP |
|
97/12553 |
|
Apr 1997 |
|
WO |
|
01/43630 |
|
Jun 2001 |
|
WO |
|
WO 01/65240 |
|
Jul 2001 |
|
WO |
|
WO 03/060462 |
|
Jul 2003 |
|
WO |
|
2005009200 |
|
Feb 2005 |
|
WO |
|
2005089065 |
|
Sep 2005 |
|
WO |
|
2006072947 |
|
Jul 2006 |
|
WO |
|
2006092797 |
|
Sep 2006 |
|
WO |
|
2006103665 |
|
Oct 2006 |
|
WO |
|
2007015255 |
|
Feb 2007 |
|
WO |
|
Other References
Rajshekhar "Continuous Impedence Monitoring During CT-Guided
Stereotactic Surgery: Relative Value in Cystic and Solid Lesions",
British Journal of Neurosurgery, 6: 439-444, 1992. cited by other
.
Misra et al. "Noninvasive Electrical Characterization of Materials
at Microwave Frequencies Using an Open-Ended Coaxial Line: Test of
An Improved Calibration Technique", IEEE Transactions on Microwave
Theory & Techniques, 38(1): 8-13, 1990. cited by other .
Burdette et al. "In Vivo Probe Measurement Technique for
Determining Dielectric Properties at VFW Through Microwave
Frequencies", IEEE Transactions on Microwave Theory &
Techniques, MTT-28(4): 414-427, 1980. cited by other .
Xu et al. "Measurement of Microwave Permittivity Using Open Ended
Elliptical Coaxial Probes", IEEE Transactions on Microwave Theory
& Techniques, 40(1): 143-150, 1992. cited by other .
Stuchly et al. "Measurement of Radio Frequency Permittivity of
Biological Tissues With an Open-Ended Coaxial Line: Part
II-Experimental Results", IEEE Transactions on Microwave Theory
& Techniques, MTT-30(1): 87-91, 1982. cited by other .
Mosig et al. "Reflection of an Open-Ended Coaxial Line", IEEE
Transactions on Instrumentation & Measurement, IM-30(1): 46-51,
1981. cited by other .
Brown "A Survey of Image Registration Techniques", ACM Computing
Surveys, 24(4): 325-376, 1992. cited by other .
U.S. Appl. No. 60,641,081, filed Jan. 4, 2005, D. Hashimshony.
cited by other .
Section on Biomedical Stochastic Physics (SBSP), "Subsurface
Spectroscopy", http://www.sbsp-limb.nichd.nih.gov/
html/spectroscopy.html. Apr. 1, 2005. cited by other .
K. Harzbecker et al., "Thermographic thorax diagnostics", Z.
Gesamte Inn. Med., Feb. 1978, 1;33(3):78-80 Abstract only (article
in German). cited by other .
Dexter Li, Kondrat'ev VB., "Thermography in different diagnosis of
lymphostasis in the lower limbs", Vestin Khir Im I. I Grek. Jun.
1976;116(6):60-4 Abstract only (article in Russian). cited by other
.
Ascension Products Ltd., MiniBIRD 500 & 800, downloaded on Mar.
15, 2005, http://www.ascension-tech.com/products/minibird.php.
cited by other .
D. Smith et al., "In Vivo Measurement of Tumor Conductiveness with
the Magnetic Bioimpedance Method", IEEE Transactions on Biomedical
Engineering, vol. 47, No. 10, Oct. 2000. cited by other .
M. Beard et al., "Size-Dependent Photoconductivity in CdSe
Nanoparticles as Measured by Time-Resolved Terahertz Spectroscopy",
Nano Letters, 2(9), 983-987, Aug. 14, 2002, Abstract only. cited by
other .
M. Akerman et al., "Nanocrystal targeting in vivo", PNAS, 99(20),
12617-12621, Oct. 1, 2002. cited by other .
A. J. Surowiec et al., "Dielectric Properties of Breast Carcinoma
and the Surrounding Tissues", IEEE Transactions on Biomedical
Engineering, vol. 35, No. 4, Apr. 1988. cited by other .
H. P. Schwan, "Mechanisms responsible for electrical properties of
tissues and cell suspensions", Medical Progress Through Technology,
19:163-165, 1993. cited by other .
J. G. Proakis et al., "Digital Signal Processing: Principles,
Algorithms, and Applications", Third Edition, Prentice Hall
International Inc., Chapter 4, Table of Contents and cover page
only. cited by other .
"Affinity Biosensors: Techniques and Protocols". Edited by K. R.
Rogers and A. Mulchandani, Humana Press, New Jersey, USA, 1998,
Table of Contents pages only. cited by other .
Journal: Biosensors & Bioelectronics, vol. 20, Issue 8, pp.
1459-1695, Feb. 15, 2005, Table of Contents pages only. cited by
other .
Journal: Biosensors & Bioelectronics, vol. 20, Issue 6, pp.
1029-1295, Dec. 15, 2004, Table of Contents pages only. cited by
other .
Journal: Biosensors & Bioelectronics, vol. 20, Issue 5, pp.
917-1028, Nov. 15, 2004, Table of Contents pages only. cited by
other .
Journal: Biosensors & Bioelectronics, vol. 20, Issue 1, pp.
1-142, Jul. 30, 2004, Table of Contents pages only. cited by other
.
Journal: Biosensors & Bioelectronics, vol. 20, Issue 12, pp.
2387-2593, Jun. 15, 2005, Table of Contents pages only. cited by
other .
Journal: Sensors & Actuators B (Chemical), vol. 103, Issues
1-2, pp. 1-473, Sep. 29, 2004, Table of Contents pages only. cited
by other .
Journal: Sensors & Actuators B (Chemical), vol. 102, Issue 1,
pp. 1-177, Sep. 2004, Table of Contents pages only. cited by other
.
Journal: Sensors & Actuators B (Chemical), vol. 106, Issue 1,
pp. 1-488, Apr. 29, 2005, Table of Contents pages only. cited by
other .
Sensors: A Comprehensive Survey--vol. 2: Chemical and Biochemical
Sensors, Part I, Edited by W. Goepel, J. Hesse, J. N. Zemel, (VCH,
1991), Table of Contents pages only. cited by other .
Sensors: A Comprehensive Survey--vol. 3: Chemical and Biochemical
Sensors, Part 2, Edited by W. Goepel, J. Hesse, J. N. Zemel, (VCH,
1992), Table of Contents pages only. cited by other .
Sensors: A Comprehensive Survey--vol. 7: Mechanical Sensors, Part
2, Edited by W. Goepel, J. Hesse, J. N. Zemel, (VCH, 1994), Table
of Contents pages only. cited by other .
Y. Kinouchi et al., "Fast in vivo Measurement of Local Tissue
Impedances Using Needle Electrodes", Med. Biol. Eng. Comput.
35(9):486-492, 1997--Abstract only. cited by other .
R. Pethig. "Dielectric and Electronic Properties of Biological
Materials", John Wiley & Sons, 1979, Cover and Table of
Contents pages only. cited by other .
S. Grimnes et al., "Bioimpedance and Bioelectricity Basics"
Academic Press, Cover and Table of Contents pages only. cited by
other .
K. S. Cole, "Membranes, Ions and Impulses": A Chapter of Classical
Biophysics, 1968, Cover and Table of Contents pages only. cited by
other .
International Search Report mailed Sep. 5, 2008. cited by
other.
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Primary Examiner: Hindenburg; Max
Assistant Examiner: Eiseman; Adam J
Attorney, Agent or Firm: Browdy and Neimark, PLLC
Parent Case Text
RELATED APPLICATIONS
This application is a National Phase Application of PCT Application
No. PCT/IL2005/000330 having International Filing Date of Mar. 23,
2005, which claims the benefit of U.S. Provisional Patent
Application No. 60/555,901, filed on Mar. 23, 2004. The contents of
the above Application are all incorporated herein by reference.
Claims
What is claimed:
1. An integrated tool, for clean-margin assessment, comprising: a
structure, which defines a proximal end with respect to a tissue
and which is adapted for placement proximally to the tissue; a
tissue-type sensor, mounted on the structure, for determining a
tissue type of a volume adjacent a tissue surface; and a
distance-measuring sensor, mounted on the structure, for
determining a distance between the tissue surface and an interface
with another tissue type, wherein the integrated tool in configured
as a hand-held tool and both the tissue-type sensor and the
distance-measuring sensor are operable in real time to provide
first measured data indicative of the tissue type of the volume
adjacent the tissue surface and second measured data indicative of
the distance from said tissue surface to the interface with another
tissue to indicate the thickness of the clean margin, said first
and second measured data providing together information for
obtaining the clean margin assessment.
2. The integrated tool of claim 1, wherein the another tissue type
is a cancerous tissue, and the integrated tool may be used to
assess: whether the tissue type at the volume adjacent the tissue
surface is healthy; and the distance between the tissue surface and
an interface with the cancerous tissue.
3. The integrated tool of claim 1, adapted for operation in tandem
with a surgical tool, for a real-time correction of a clean margin,
where necessary.
4. The integrated tool of claim 1, and further including an
incision instrument, integrated therewith, for a real-time
correction of a clean margin, where necessary.
5. The integrated tool of claim 4, wherein the incision instrument
may be selectively retracted and selectively deployed.
6. The integrated tool of claim 4, wherein the incision instrument
is a diathermial incision instrument.
7. The integrated tool of claim 1, wherein the tissue-type sensor
is selected from the group consisting of a sensor for tissue
electromagnetic properties, a dielectric sensor, an impedance
sensor, a sensor for optical fluorescence spectroscopy, a sensor
for optical reflectance spectroscopy, an MRI sensor, an RF sensor,
an MW sensor, a temperature sensor, and infrared thermography
sensor.
8. The integrated tool of claim 1, wherein the tissue-type sensor
is a dielectric-property sensor, formed substantially as a coaxial
cable.
9. The integrated tool of claim 1, wherein the tissue surface is
selected from the group consisting of a skin, a tissue lumen, and
an incision surface.
10. The integrated tool of claim 1, wherein the distance-measuring
sensor is an ultrasound transducer.
11. The integrated tool of claim 1, wherein the distance-measuring
sensor is formed of two ultrasound transducers.
12. The integrated tool of claim 1, wherein the distance-measuring
sensor is formed of an array of ultrasound transducers, which may
be selectively steered.
13. The integrated tool of claim 1, wherein the distance-measuring
sensor is selected from the group consisting of a strain gauge and
a pressure sensor.
14. The integrated tool of claim 1, wherein the distance-measuring
sensor is an MRI probe.
15. The integrated tool of claim 1, operative with a guide wire,
wherein a proximal tip of the guide wire, with respect to the
tissue, is placed within the another tissue type.
16. The integrated tool of claim 1, operative with a guide wire,
wherein a proximal tip of the guide wire, with respect to the
tissue, is placed in close proximity with the another tissue
type.
17. The integrated tool of claim 1, operative with a guide wire,
wherein the distance-measuring sensor is an ultrasound transducer,
and the guide wire further includes a guide wire ultrasound
transducer, at a proximal tip thereof, with respect to the tissue,
for emitting ultrasound signals, indicative of the proximal-tip
distance from the integrated tool.
18. The integrated tool of claim 1, operative with a guide wire,
wherein the distance-measuring sensor is an ultrasound transducer,
and the guide wire further includes a guide wire ultrasound
transducer, at a proximal tip thereof, with respect to the tissue,
for emitting ultrasound signals, indicative of the proximal-tip
position with respect to the integrated tool, by triangulation.
19. The integrated tool of claim 1, and further including a
position-tracking device.
20. The integrated tool of claim 19, wherein the position-tracking
device is correlated with a coordinate system of a fixed frame,
within which, the tissue is held fixed in place.
21. A system for clean-margin assessment, comprising: a hand-held,
integrated tool, for clean-margin assessment, which comprises: a
structure, which defines a proximal end with respect to a tissue
and which is adapted for placement proximally to the tissue; a
tissue-type sensor, mounted on the structure, for determining a
tissue type of a volume adjacent a tissue surface; and a
distance-measuring sensor, mounted on the structure, for
determining a distance between the tissue surface and an interface
with another tissue type; and a computerized system, which
comprises: a tissue-type sensor analyzer, associated with the
tissue-type sensor; a distance-measuring analyzer, associated with
the distance-measuring sensor; and an output device, which provides
output of measurements by the tissue-type sensor and the
distance-measuring sensor to indicate the thickness of a clean
margin.
22. The system of claim 21, wherein the another tissue type is a
cancerous tissue, and the integrated tool may be used to assess:
whether the tissue type at the volume adjacent the tissue surface
is healthy; and the distance between the tissue surface and an
interface with the cancerous tissue.
23. The system of claim 21, and further including a fixed frame for
holding the tissue therein.
24. The system of claim 21, and further including a
position-tracking device and a position-tracking-device
analyzer.
25. The system of claim 21, and further including a computer.
26. A system for clean-margin assessment, comprising: A fixed frame
for holding a tissue therein, the frame defining a coordinate
system; a hand-held, integrated tool, for clean-margin assessment,
which comprises: a structure, which defines a proximal end with
respect to a tissue and which is adapted for placement proximally
to the tissue; a tissue-type sensor, mounted on the structure, for
determining a tissue type of a volume adjacent a tissue surface;
and an imager, operative as a distance-measuring sensor, mounted on
the structure, for determining a distance between the tissue
surface and an interface with another tissue type; a
position-tracking device, mounted on the structure and correlated
with the coordinate system; and a computerized system, which
comprises: a tissue-type sensor analyzer, associated with the
tissue-type sensor; a distance-measuring analyzer, associated with
the distance-measuring sensor; a position-tracking device analyzer,
associated with the position-tracking device; a computer, for
receiving data from the tissue-type sensor analyzer, the
distance-measuring sensor analyzer, and the position-tracking
device analyzer, and performing analysis thereof to assess a clean
margin status; and an output device, associated with the
computer.
27. A method of clean-margin assessment, comprising: providing a
hand-held, integrated tool, for clean-margin assessment, which
comprises: a structure, which defines a proximal end with respect
to a tissue and which is adapted for placement proximally to the
tissue; a tissue-type sensor, mounted on the structure, for
determining a tissue type of a volume adjacent a tissue surface;
and a distance-measuring sensor, mounted on the structure, for
determining a distance between the tissue surface and an interface
with another tissue type; determining the tissue type at the volume
adjacent the tissue surface; determining the distance between the
tissue surface and the interface with the another tissue type; and
outputting an indication of margin thickness to assess clean margin
status.
28. A method of clean-margin assessment, comprising: providing a
hand-held, integrated tool, for clean-margin assessment, which
comprises: a structure, which defines a proximal end with respect
to a tissue and which is adapted for placement proximally to the
tissue; a tissue-type sensor, mounted on the structure, for
determining a tissue type at a near zone volume of a tissue
surface; a non-invasive imager, mounted on the structure; and a
position-tracking device, mounted on the structure; fixing the
tissue within a fixed frame, which defines a coordinate system;
imaging the tissue, from at least two locations and orientations,
by the hand-held, integrated tool; reconstructing a three
dimensional image of the tissue; displaying the three dimensional
image of the tissue; defining a desired clean margin around another
tissue type; displaying the desired clean margin; calculating a
recommended incision path; displaying the recommended incision
path; providing an incision instrument; cutting along the
recommended incision path; and determining the tissue type at the
near zone volume of the tissue surface, by the hand-held,
integrated tool.
29. The method of claim 28, and further including: continuously
imaging the tissue, from different locations and orientations along
the tissue surface, by the hand-held, integrated tool; continuously
correcting the recommended incision path; and continuously
displaying the continuously corrected recommended incision
path.
30. The method of claim 29, and further including continuously
determining the tissue type, at the volume adjacent the incision
surface, by the hand-held, integrated tool.
31. An integrated tool, for clean-margin assessment, comprising: a
structure, which defines a proximal end with respect to a tissue
and which is adapted for placement proximally to the tissue; a
tissue characterization sensor of a first type, mounted on the
structure, for determining a tissue type of a volume adjacent a
tissue surface; and a distance-measuring sensor of a second type,
mounted on the structure, for determining a distance between the
tissue surface and an interface with another tissue type, wherein
the integrated tool is configured as a hand-held tool, and both the
tissue characterization sensor and the distance-measuring sensor
are operable in real time to provide first measured data indicative
of the tissue characterization of the volume adjacent the tissue
surface and second measured data indicative of the distance from
said tissue surface to the interface with another tissue to
indicate the thickness of the clean margin, said first and second
measured data providing together information for obtaining the
clean margin assessment.
32. An integrated tool according to claim 31, wherein the tissue
characterization sensor is selected from the group consisting of a
sensor for tissue electromagnetic properties, a dielectric sensor,
an impedance sensor, a sensor for optical fluorescence
spectroscopy, a sensor for optical reflectance spectroscopy, an MRI
sensor, an RF sensor, an MW sensor, a temperature sensor, and
infrared thermography sensor.
33. An integrated tool according to claim 31, wherein the
distance-measuring sensor is selected from the group consisting of
an ultrasound transducer, a strain gauge, a pressure sensor and an
MRI probe.
34. A system for assessment of a clean margin around a mass of
unhealthy tissue, said system comprising: an integrated tool, for
clean-margin assessment, said tool comprising: a structure, which
defines a proximal end with respect to a tissue and which is
adapted for placement proximally to the tissue; a tissue-type
sensor, mounted on the structure, for determining a tissue type of
a volume adjacent a tissue surface; and a distance-measuring
sensor, mounted on the structure, for determining a distance
between the tissue surface and an interface with another tissue
type, wherein the integrated tool is configured as a hand-held
tool; and an output system providing an indication of the thickness
of the margin between the tissue surface and the interface with the
other tissue type.
Description
FIELD AND BACKGROUND OF THE INVENTION
The present invention relates generally, to a medical tool for
tissue characterization, and specifically, to an integrated tool,
having a tissue-type sensor, for determining the tissue type at an
incision edge, and a distance-measuring sensor, for determining the
distance to an interface with another tissue type. The tool is
operable for confirming an existence of a clean margin of healthy
tissue around an excised tumor, and for determining the width of
the margin.
When a malignant tumor is found in a breast, the patient currently
has two primary treatment options, 1) mastectomy or 2) breast
conserving therapy, which means, lumpectomy, followed by radiation
therapy. Generally, breast conserving therapy is indicated for
patients with Stage T1 or T2 cancers, of between less then about
0.5 and about 5 cm in greatest dimension.
To localize the tumor within the breast, a radiologist may place a
guide wire under x-ray or ultrasound guidance, so that the proximal
tip of the guide wire, with respect to the tissue, is in the tumor.
Alternatively, an imaging modality alone, for example, mammography,
CT, ultrasound, or another imaging modality may be used to locate
the tumor. The patient is then transported to the operating room,
where the surgeon uses the guide wire, or the image, or palpation
to locate the tumor in the breast and to excise a portion of tissue
including the cancerous portion and a layer of healthy tissue
surrounding the cancerous portion.
The layer of healthy tissue must enclose the cancerous portion, to
ensure that all the malignancy has been removed. This layer is
often referred to as a "clean margin." Although generally dependent
on the size and shape of the malignant tumor that is being removed,
a desired depth of the clean margin may range from 1 cell layer, or
about 40 microns, to 10 mm.
Typically the surgeon uses a scalpel and (or) an electrosurgical
cutting device to remove a tissue portion enclosing the tumor, in
one piece, and manage bleeding. The removed portion is transported
to the pathologist, who samples the margins, histologically, at
specific and suspicious points, for example, at one or a few
representative points on each face of the portion, to assess
whether the cancer has been completely removed from the body. If
the pathologists deems that cancer cells are too close to the edge
of the portion, i.e., if he deems the margin infected, a
re-excision is recommended, and the patient must undergo a second
surgical procedure to remove more of the tissue.
There are several problems with conventional breast conserving
therapy. 1. There are technical challenges associated with
placement of the guide wire tip, and the radiologist may not place
the guide wire properly through the lesion. It is particularly
difficult to place the guide wire at the correct depth. Also, when
the guide wire is placed under x-ray guidance, the breast is
compressed. When the breast is decompressed for the surgical
excision, the guide wire can move, resulting in inaccurate
placement thereof. Finally, the guide wire placement procedure is
uncomfortable to the patient and logistically challenging; the
procedure must be coordinated with the time of surgery. Often, the
easiest path for the radiologist to place the guide wire is
different from the best surgical approach, so the surgeon cannot
follow the guide wire down to the tumor. 2. It is difficult to
estimate correctly the full extent of the disease and the exact
volume of the cancerous portion of the tumor, especially with
non-palpable lesions. Non-palpable lesions are similar in their
properties to normal tissue, hence harder to detect by ultrasound
and mammography. Thus, the guide wire may be inaccurately placed.
To compensate for the imprecision in determining the extent of the
disease, the surgeon must remove much more tissue than would be
required if the full extent of the cancer could be imaged in
real-time. This leads to a negative impact aesthetically and
emotionally on the patient.
U.S. Pat. No. 6,546,787 to Schiller et al., whose disclosure is
incorporated herein by reference, provides an apparatus and method
for detecting a distance from a tissue edge to a malignant tissue,
enclosed therein. The apparatus comprises a needle having a strain
gage, mounted on one of the needles walls. Strain signals are
collected as the needle is moved through the tissue. The needle is
inserted at different points to allow data collection from
different points within the tissue. The data is sent together with
its spatial coordinates to a computerized system, which provides an
image of the structure of the examined tissue.
WO Patent 9712553 to Changus et al., whose disclosures is
incorporated herein by reference, provides an apparatus for marking
a predetermined margin around a tumor that is contained within a
healthy tissue. The apparatus includes a needle to be inserted into
the patient's body towards the malignant tissue. The needle
contains margin wires that are to create a cage containing the
malignant tissue within it. The needle is to reach a predetermined
distance of between 7 and 13 mm and preferably 10 mm from the
malignant tissue before the wires are deployed to create the cage.
The cage is then used to guide the surgeon performing a lumpectomy
procedure, as to the portion of tissue to be excised and its
location, so that the removed tissue will include the malignant
tissue with a sufficient clean margin around it. The drawback of
such a procedure is that it requires exact knowledge as to the
location of the malignant tissue and its boundaries while creating
the cage.
US Patent applications 20040168692 and 20020059938, and U.S. Pat.
Nos. 6,752,154, 6,722,371, 6,564,806, 6,405,733, all to Fogarty, et
al., all entitled, "Device for accurately marking tissue," and all
of whose disclosures are incorporated herein by reference, describe
methods and a device for fixedly yet removably marking a volume of
tissue containing a suspect region for excision. Additionally they
describe methods for deployment of the device and its excision
along with the marked tissue volume. At least one locator element
is deployed into tissue and assumes a predetermined curvilinear
shape to define a tissue border containing a suspect tissue region
along a path. The locator element path preferably encompasses the
distal-most portion of the tissue volume, with respect to the tool,
without penetrating that volume. Multiple locator elements may be
deployed to further define the tissue volume along additional paths
defining the tissue volume border that do not penetrate the volume.
Other localization wire embodiments of the invention are disclosed
in which the tissue volume may be penetrated by a portion of the
device. Polar and tangential deployment configurations as well as a
locator element that may be cold-formed by a die in the distal
portion of the deployment tube into a permanent accurate shape are
also disclosed.
US Patent applications 20050010131 and U.S. Pat. Nos. 6,331,166 and
6,699,206, all to Burbank et al., all of whose disclosures are
incorporated herein by reference, describe a method and apparatus
for precisely isolating a target lesion in a tissue, so that there
is a high likelihood the lesion is removed with a margin. The
apparatus comprises a biopsy instrument having a distal end (with
respect to operator) adapted for entry into the patient's body, a
longitudinal shaft, and a cutting element disposed along the shaft.
The cutting element is actuatable between a radially retracted and
extended position. Advantageously, the instrument is rotatable
about its axis in the radially extended position to isolate a
desired tissue specimen from surrounding tissue by defining a
peripheral margin about the tissue specimen. Once the tissue
specimen is isolated, it may be segmented by further manipulation
of the cutting element, after which the tissue segments are
preferably individually removed from the patient's body through a
cannula or the like. Alternatively, the specimen may be
encapsulated and removed as an intact piece.
U.S. Pat. No. 6,840,948 to Albrecht et al, whose disclosure is
incorporated herein by reference, discloses a device and method for
removal of tissue lesions, for example, in the breast, the liver
and the lungs. The device includes a probe housing having a
rotatable RF loop cutter mounted at the distal end of the probe.
The RF loop cutter can include at least one electrode supplied with
an RF actuating signal for cutting tissue. A rotational drive and
specimen containment sheath can also be included. Real-time imaging
is preferably used with the RF loop probe to assist in placement of
the probe, and to more accurately assess a desired excision
volume.
Ultrasound or ultrasonography is a medical imaging technique, using
high frequency sound waves in the range of about 1 to 20 MHz and
their echoes. The sound waves travel in the body and are reflected
by interfaces between different types of tissues, such as between a
healthy tissue and a denser cancerous tissue, or between a soft
tissue and a bone. The ultrasound probe receives the reflected
sound waves and the associated instrumentation calculates the
distances from the probe to the reflecting boundaries.
Ultrasound probes are formed of piezoelectric crystal, which
produces an electric signal in response to a pressure pulse. The
shape of the probe determines its field of view, and the frequency
of the emitted sound determines the minimal detectable object size.
Generally, the probes are designed to move across the surface of
the body. However, some probes are designed to be inserted through
body. lumens, such as the vagina or the rectum, so as to get closer
to the organ being examined.
The calculation of the distance, d, is based on the speed of sound
in the tissue, v, (for example, in fat 1450 m/s, in blood 1570 m/s,
in skull bone 4080 m/s, while the mean value for human soft tissue
is 1540 m/s, which is similar to that of water) and the time of
travel, t, usually measured in microseconds. Where a single probe
is used as a transmitter and receiver, the time of travel, t,
refers to the time it takes the sound signal to propagate through
the tissue from the ultrasound probe to the reflecting interface
and back to the ultrasound probe. Thus, in a homogeneous media, the
distance may be calculated according to d=v t/2.
It will be appreciated that a predetermined offset needs to be
considered, due to fixed electronic and mechanical delays. For
example, in cases of measurements involving direct contact
transducers, the offset compensates for transit time of the sound
pulse through the transducer's wear-plate and the couplant layer,
and for any electronic switching time or cable delays. The offset
is determined as a part of instrument calibration procedures and is
necessary for high accuracy. It will be further appreciated that
when a single transducer transmits and receives, there is an
additional dead time, which can be overcome by using at least two
transducers, one transmitting and the other receiving.
A reflectance, R, may be defined, representing the energy that is
being reflected. R depends on the impedance discontinuity between
the different types of tissues across the interface, or
R=(Z.sub.2-Z.sub.1).sup.2/(Z.sub.2+Z.sub.1).sup.2,
where Z.sub.1 is the acoustic impedance of the tissue in which the
ultrasound pulse travels, and Z.sub.2 is the impedance of the
tissue across the interface. In general, the acoustic impedance is
the product of the density of a material, .rho., and the speed of
sound in that material, v, so that, Z=.rho.v.
For tissues, which are essentially water-like, so that the speed of
sound in them is essentially that of the speed of sound in water,
the reflectance depends on the variation in tissue density
.rho..sub.1 and .rho..sub.2, across the interface.
For example, in a human body, at ultrasound frequencies of several
MHz, for example, 1-10 MHz, the density variation between fat and
muscle tissue will lead to about 3% reflection because of the
difference in ultrasonic impedance between the two types of tissue.
Similarly, at these frequencies, a breast tumor, being denser than
fat, will lead to a reflection of about 1%. Thus, the ultrasound
technique is useful in identifying cancerous tumors. A radiologist
may use the ultrasound imaging to guide a surgical tool, such as a
biopsy needle or an incision instrument.
Before the early 1970's ultrasound imaging systems were able to
record only the strong echoes arising from the outlines of an
organ, but not the low-level echoes of the internal structure.
Therefore liver scans, for instance, did not show possible
carcinomas or other pathological states. In 1972 a refined imaging
mode was introduced called gray-scale display, in which the
internal texture of many organs became visible. In gray-scale
display, low-level echoes are amplified and recorded together with
the higher-level ones, giving many degrees of brightness. In
consequence, ultrasound imaging became a useful tool for imaging
tumors, for example, in the liver.
A development of recent years is a 3D ultrasound imaging, in which,
several two-dimensional images are acquired by moving the probes
across the body surface or by rotating probes, inserted into body
lumens. The two-dimensional scans are then combined by specialized
computer software to form 3D images.
In multiple-element probes, each element has a dedicated electric
circuit, so that the beam can be "steered" by changing the timing
in which each element sends out a pulse. Additionally,
transducer-pulse controls allow the operator to set and change the
frequency and duration of the ultrasound pulses, as well as the
scan mode of the machine. A probe formed of array transducers has
the ability to be steered as well as focused. By sequentially
stimulating each element, the beams can be rapidly steered from the
left to right, to produce a two-dimensional cross sectional
image.
Contrast agents may be used in conjunction with ultrasound imaging,
for example as taught by U.S. Pat. No. 6,280,704, to Schutt, et
al., entitled, "Ultrasonic imaging system utilizing a
long-persistence contrast agent," whose disclosure is incorporated
herein by reference.
A large number of techniques, other than ultrasound, are available
today for tissue characterization, to determine the presence of
abnormal tissue, for example, cancerous or pre-cancerous tissue.
Many of these may be used with hand-held probes. Others use
miniature probes that may be inserted into a body lumen or applied
in minimally invasive surgery.
One of the methods used for tissue characterization is based on
measurements of the tissue's electro-magnetic properties.
Commonly owned U.S. Pat. No. 6,813,515, to Hashimshony, entitled,
"Method and system for examining tissue according to the dielectric
properties thereof," whose disclosure is incorporated herein by
reference, describes a method and system for examining tissue in
order to differentiate it from other tissue, according to the
dielectric properties of the examined tissue. The method includes
applying an electrical pulse to the tissue to be examined via a
probe formed with an open cavity such that the probe generates an
electrical fringe field in examined tissue within the cavity and
produces a reflected electrical pulse therefrom with negligible
radiation penetrating into other tissues or biological bodies near
the examined tissue; detecting the reflected electrical pulse; and
comparing electrical characteristics of the reflected electrical
pulse with respect to the applied electrical pulse to provide an
indication of the dielectric properties of the examined tissue.
Furthermore, commonly owned U.S. Patent Application 60/641,081,
entitled, "Device and Method for Tissue Characterization in a Body
Lumen, by an Endoscopic Electromagnetic Probe," whose disclosure is
incorporated herein by reference, discloses a device and method for
tissue characterization in a body lumen, for the detection of
abnormalities, using an electromagnetic probe, mounted on an
endoscope. The endoscope may be designed for insertion in a body
lumen, selected from the group consisting of an oral cavity, a
gastrointestinal tract, a rectum, a colon, bronchi, a vagina, a
cervix, a urinary tract, and blood vessels. Additionally, it may be
designed for insertion in a trucar valve.
Electrical impedance imaging is another known imaging technique for
detecting tumors. It involves systems in which the impedance
between a point on the surface of the skin and some reference point
on the body of a patient is determined. Sometimes, a multi-element
probe, formed as a sheet with an array of electrical contacts is
used, for obtaining a two-dimensional impedance map of the tissue,
for example, the breast. The two-dimensional impedance map may be
used, possibly in conjunction with other data, such as mammography,
for the detection of cancer.
Rajshekhar, V. ("Continuous impedance monitoring during CT-guided
stereotactic surgery: relative value in cystic and solid lesions,"
Rajshekhar, V., British Journal of Neurosurgery, 1992, 6, 439-444)
describes using an impedance probe with a single electrode to
measure the impedance characteristics of lesions. The objective of
the study was to use the measurements made in the lesions to
determine the extent of the lesions and to localize the lesions
more accurately. The probe was guided to the tumor by CT and four
measurements were made within the lesion as the probe passed
through the lesion. A biopsy of the lesion was performed using the
outer sheath of the probe as a guide to position, after the probe
itself was withdrawn.
U.S. Pat. No. 4,458,694, to Sollish, et al., entitled, "Apparatus
and method for detection of tumors in tissue," whose disclosure is
incorporated herein by reference, relates to an apparatus for
detecting tumors in human breast, based on the dielectric constants
of localized regions of the breast tissue. The apparatus includes a
probe, comprising a plurality of elements. The apparatus further
includes means for applying an AC signal to the tissue, means for
sensing electrical properties at each of the probe elements at
different times, and signal processing circuitry, coupled to the
sensing means, for comparing the electrical properties sensed at
the different times. The apparatus thus provides an output of the
dielectric constants of localized regions of breast tissue
associated with the probe.
Similarly, U.S. Pat. No. 4,291,708 to Frei, et al., entitled,
"Apparatus and method for detection of tumors in tissue," whose
disclosure is incorporated herein by reference, relates to
apparatus for detecting tumors in human breast tissue, by the
dielectric constants of a plurality of localized regions of human
breast tissue.
U.S. Pat. Nos. 6,308,097, 6,055,452 and 5,810,742, to Pearlman, A.
L., entitled, "Tissue characterization based on impedance images
and on impedance measurements," whose disclosures are incorporated
herein by reference, describe apparatus for aiding in the
identification of tissue type for an anomalous tissue in an
impedance image. The device comprises: means for providing a
polychromic emmitance map of a portion of the body; means for
determining a plurality of polychromic measures from one or both of
a portion of the body; and a display of an indication based on said
plurality of polychromic measures.
Another known method of tissue characterization is by optical
fluorescence spectroscopy. When a sample of large molecules is
irradiated, for example, by laser light, it will absorb radiation,
and various levels will be excited. Some of the excited states will
return back substantially to the previous state, by elastic
scattering, and some energy will be lost in internal conversion,
collisions and other loss mechanisms. However, some excited states
will create fluorescent radiation, which, due to the distribution
of states, will give a characteristic wavelength distribution.
Some tumor-marking agents give well-structured fluorescence
spectra, when irradiated by laser light. In particular,
hematoporphyrin derivatives (HPD), give a well-structured
fluorescence spectrum, when excited in the Soret band around 405
nm. The fluorescence spectrum shows typical peaks at about 630 and
690 nm, superimposed in practice on more unstructured tissue auto
fluorescence. Other useful tumor-marking agents are
dihematoporphyrin ether/ester (DHE), hematoporphyrin (HP),
polyhematoporphyrin ester (PHE), and tetrasulfonated phthalocyanine
(TSPC), when irradiated at 337 nm (N.sub.2 laser).
U.S. Pat. No. 5,115,137, to Andersson-Engels, et al, entitled,
"Diagnosis by means of fluorescent light emission from tissue,"
whose disclosure is incorporated herein by reference, relates to
improved detection of properties of tissue by means of induced
fluorescence of large molecules. The tissue character may then be
evaluated from the observed large-molecule spectra. According to
U.S. Pat. No. 5,115,137, the spectrum for tonsil cancer is clearly
different from normal mucosa, due to endogenous porphyrins.
Similarly, U.S. Pat. No. 4,785,806, to Deckelbaum, entitled, "Laser
ablation process and apparatus," whose disclosure is incorporated
herein by reference, describes a process and apparatus for ablating
atherosclerotic or neoplastic tissues. Optical fibers direct low
power light energy at a section of tissue to be ablated to cause
the section to fluoresce. The fluorescence pattern is analyzed to
determine whether the fluorescence frequency spectrum is
representative of normal or abnormal tissue. A source of high
power, ultraviolet, laser energy directed through an optical fiber
at the section of tissue is fired only when the fluorometric
analysis indicates that it is directed at abnormal tissue.
Additionally, U.S. Pat. No. 4,682,594, to Mok, entitled, "Probe-and
fire lasers," whose disclosure is incorporated herein by reference,
describes a method and an apparatus of irradiating a treatment area
within a body, such as blood vessel plaque. The method includes
initially administering to the patient a non-toxic
atheroma-enhancing reagent which causes the plaque to have a
characteristic optical property when illuminated with a given
radiation, introducing a catheter system including fiberoptic cable
means into the artery such that the distal end thereof is
operatively opposite the plaque site, introducing into the proximal
end of the fiberoptic cable means the given radiation,
photoelectrically sensing at the proximal end the characteristic
optical property to generate a control signal, and directly under
the control of the control signal transmitting via the cable means
from the proximal end to the distal end, periodically occurring
laser pulses until the characteristic optical property is no longer
sensed.
U.S. Pat. No. 6,258,576, to Richards-Kortum, et al., entitled,
"Diagnostic method and apparatus for cervical squamous
intraepithelial lesions in vitro and in vivo using fluorescence
spectroscopy," whose disclosure is incorporated herein by
reference, relates to the use of multiple illumination wavelengths
in fluorescence spectroscopy for the diagnosis of cancer and
precancer, for example, in the cervix. In this manner, it has been
possible to (i) differentiate normal or inflamed tissue from
squamous intraepithelial lesions (SILs) and (ii) differentiate high
grade SILs from non-high grade SILs. The detection may be performed
in vitro or in vivo. Multivariate statistical analysis has been
employed to reduce the number of fluorescence excitation-emission
wavelength pairs needed to re-develop algorithms that demonstrate a
minimum decrease in classification accuracy. For example, the
method of the aforementioned patent may comprise illuminating a
tissue sample with electromagnetic radiation wavelengths of about
337 nm, 380 nm and 460 nm, to produce fluorescence; detecting a
plurality of discrete emission wavelengths from the fluorescence;
and calculating from the emission wavelengths a probability that
the tissue sample belongs in particular tissue classification.
Commonly owned U.S. Patent Application 2003/01383786, to
Hashimshony, entitled, "Method and apparatus for examining tissue
for predefined target cells, particularly cancerous cells, and a
probe useful for such method and apparatus," whose disclosure is
incorporated herein by reference, teaches a method apparatus and
probe for examining tissue and characterizing its type according to
measured changes in optical characteristics of the examined tissue.
In a preferred embodiment of this method the tissue to be examined
is subject to a contrast agent containing small particles of a
physical element conjugated with a biological carrier selectively
bindable to the target cells. Additionally, energy pulses are
applied to the examined tissue, and the changes in impedance and/or
the optical characteristics produced by the applied energy pulses
are detected and utilized for determining the presence of the
target cells in the examined tissue. Furthermore, in a preferred
embodiment, the applied energy pulses include laser pulses, and the
physical element conjugated with a biological carrier is a
light-sensitive semiconductor having impedance which substantially
decrease in the presence of light. Moreover, the same probe used
for detecting the targeted cells, may also be used for destroying
the cells so targeted.
Optical reflectance spectroscopy may also be used. Its application
for tissue characterization is described, for example, in
http://www.sbsplimb.nichd.nih.gov/html/spectroscopy.html,
downloaded on Mar. 15, 2005. It describes an optical reflectance
spectroscopy (ORS) device for measuring the thickness of the
epithelial layer, and an evaluation technique based on oblique
angle reflectance spectroscopy that allows assessment of the
scattering and absorption properties of the epithelium and stroma,
thus providing information on chronic oral epithelial tissue
inflammation, which is considered a potential diagnostic precursor
to oral cancer.
Another known method for tissue characterization is magnetic
resonance imaging (MRI), which is based on the absorption and
emission of energy in the radio frequency range of the
electromagnetic spectrum, by nuclei having unpaired spins.
Conventional MRI is a large-apparatus, for whole body imaging,
having:
i. a primary magnet, which produces the B.sub.o field for the
imaging procedure;
ii. gradient coils for producing a gradient in B.sub.o;
iii. an RF coil, for producing the B.sub.1 magnetic field,
necessary to rotate the spins by 90.degree. or 180.degree. and for
detecting the MRI signal; and
iv. a computer, for controlling the components of the MRI
imager.
Generally, the magnet is a large horizontal bore superconducting
magnet, which provides a homogeneous magnetic field in an internal
region within the magnet. A patient or object to be imaged is
usually positioned in the homogeneous field region located in the
central air gap for imaging. A typical gradient coil system
comprises an anti-Helmholtz type of coil. These are two parallel
ring shaped coils, around the z axis. Current in each of the two
coils flows in opposite directions creating a magnetic field
gradient between the two coils.
The RF coil creates a B1 field, which rotates the net magnetization
in a pulse sequence. The RF coils may be: 1) transmit and receive
coils, 2) receive only coils, and 3) transmit only coils.
As described hereinabove, the MRI relies on a magnetic field in an
internal region within the magnet. As such, it is unsuitable as a
handheld probe or an endoscopic probe, because the tissue to be
imaged has to be in the internal region of the imager,
This problem has been resolved by U.S. Pat. No. 5,572,132, to
Pulyer, et al., entitled, "MRI probe for external imaging," whose
disclosure is incorporated herein by reference, which describes an
MRI spectroscopic probe having an external background magnetic
field B0 (as opposed to the internal background magnetic filed of
the large horizontal bore superconducting magnet.). Thus, an MRI
catheter for endoscopical imaging of tissue of the artery wall,
rectum, urinal tract, intestine, esophagus, nasal passages, vagina
and other biomedical applications may be constructed. The probe
comprises (i) a miniature primary magnet having a longitudinal axis
and an external surface extending in the axial direction, and (ii)
a RF coil surrounding and proximal to said surface. The primary
magnet is structured and configured to provide a symmetrical,
preferably cylindrically shaped, homogeneous field region external
to the surface of the magnet. The RF coil receives NMR signals from
excited nuclei. For imaging, one or more gradient coils are
provided to spatially encode the nuclear spins of nuclei excited by
an RF coil, which may be the same coil used for receiving NMR
signals or another RF coil.
Additionally, commonly owned U.S. Patent Application 2005/0021019
to Hashimshony et al., entitled "Method and apparatus for examining
substance, particularly tissue, to characterize its type," whose
disclosure is incorporated herein by reference, describes a method
and apparatus for examining a substance volume to characterize its
type, by: applying a polarizing magnetic field through the examined
substance: applying RF pulses locally to the examined substance
volume such as to invoke electrical impedance (EI) responses
signals corresponding to the electrical impedance of the substance,
and magnetic resonance (MR) responses signals corresponding to the
MR properties of the substance; detecting the EI and MR response
signals; and utilizing the detected response signals for
characterizing the examined substance volume type.
Contrast agents may be used in conjunction with MRI. For example,
U.S. Pat. No. 6,315,981 to Unger, entitled, "Gas filled
microspheres as magnetic resonance imaging contrast agents," whose
disclosure is incorporated herein by reference, describes the use
of gas filled microspheres as contrast agents for MRI.
Temperature imaging for locating and detecting neoplastic tissue is
also known. In the 1950's, it was discovered that the surface
temperature of skin in the area of a malignant tumor exhibited a
higher temperature than that expected of healthy tissue. Thus, by
measuring body skin temperatures, it became possible to screen for
the existence of abnormal body activity such as cancerous tumor
growth. With the development of liquid crystals and methods of
forming temperature responsive chemical substrates, contact
thermometry became a reality along with its use in medical
applications. Devices employing contact thermometry could sense and
display temperature changes through indicators which changed
colors, either permanently or temporarily, when placed in direct
physical contact with a surface such as skin, reflecting a
temperature at or near the point of contact. An abnormal reading
would alert a user to the need for closer, more detailed
examination of the region in question. However, the art in this
area has been directed primarily at sensing and displaying
temperatures on exterior skin surfaces. Thus, for example, U.S.
Pat. No. 3,830,224, to Vanzetti et al., whose disclosure is
incorporated herein by reference, disclosed the placement of
temperature responsive, color changing liquid crystals at various
points in a brassiere for the purpose of detecting the existence of
breast cancer, while US Patent RE 32,000, to Sagi, entitled,
"Device for Use in Early Detection of Breast Cancer," whose
disclosure is incorporated herein by reference, disclosed the use
of radially arranged rows of temperature responsive indicators,
deposited on a disc for insertion into the breast-receiving cups of
a brassiere for the same purpose.
U.S. Pat. No. 6,135,968, to Brounstein, entitled, "Differential
temperature measuring device and method", whose disclosure is
incorporated herein by reference, describes a device and method for
sensing temperatures at internal body locations non-surgically
accessible only through body orifices. The device is particularly
useful in medical applications such as screening for cancer and
other abnormal biological activity signaled by an increase in
temperature at a selected site. As applied to prostate
examinations, the device is temporarily, adhesively affixed to a
user's fingertip or to a mechanical probe. In the preferred
embodiment, the device includes two temperature-sensing elements,
which may include a plurality of chemical indicators. Each
indicator changes color in response to detection of a predetermined
particular temperature. When properly aligned and installed, the
first element is located on the palmar surface of the fingertip
while the second element is located on the dorsal surface of the
fingertip. After an examination glove has been donned over the
fingertip carrying the device, a prostate examination is performed
during which the first element is brought into constant but brief
contact with the prostate region and the second element is
similarly, simultaneously brought into contact with a dermal
surface opposing the prostate region. Upon withdrawal of the
fingertip from the rectum and removal of the glove, the two
temperature sensing elements may be visually examined in order to
determine the temperatures detected by each one. A significant
difference in observed temperatures indicates the possibility of
abnormal biological activity and the need for further diagnostic or
medical procedures.
Infrared thermography is a temperature imaging technique, which
measures thermal energy emitted from the body surface without
contact, quickly and dynamically, and produces a temperature image
for analysis. Harzbecker K, et al. report, based on thermic
observations in 63 patients and a control experiment in 15 persons,
on experiences with thermography in the diagnosis of diseases,
which are localized more profoundly in the thoracic cavity.
(Harzbecker K, et al., "Thermographic thorax diagnostics," Z
Gesamte Inn Med. Feb. 1, 1978;33(3):78-80.)
Similarly, Dexter L I, Kondrat'ev V B. report data concerning the
use of lymphography and thermography for the purpose of
establishing a differential diagnosis in 42 patients with edema of
the lower limbs of a different origin. A comparative estimation of
different methods of the differential diagnosis indicated the
advantages of infrared thermography. (Dexter L I, Kondrat'ev V B.,
"Thermography in differential diagnosis of lymphostasis in the
lower limbs," Vestn Khir Im I I Grek. June 1976; 116(6):60-4.)
Various means for minimally invasive surgical removal, of a breast
tumor and other tumors in a soft tissue are known.
For example, U.S. Pat. No. 6,375,634, to Carroll, entitled,
apparatus and method to encapsulate, kill and remove malignancies,
including selectively increasing absorption of x-rays and
increasing free-radical damage to residual tumors targeted by
ionizing and non-ionizing radiation therapy", whose disclosure is
incorporated herein by reference, describes a coaxial bipolar
needle electrode for applying radio-frequency diathermal heat.
U.S. Pat. No. 6,840,948 to Albrecht, et al. entitled, "Device for
removal of tissue lesions," whose disclosure is incorporated herein
by reference, describes an excisional biopsy device and method for
excision and removal of neoplasms under real-time image guidance
with minimal disruption of normal tissue while providing an optimal
specimen to assess the completeness of the excision. The device and
method are minimally invasive, and are used to remove cancerous
lesions from soft tissue, including breast tissue, and are a less
invasive alternative to open lumpectomy. The invention provides an
RF loop for excision and removal of breast lesions which promotes
hemostasis during excision through electrosurgical coagulation of
blood vessels and channels to supply pressure and hemostatic fluids
to the tissue cavity.
The method includes is as follows: The mass is localized, and the
tunneling trajectory is determined. The skin is excised, and
tunneling is begun by activating and using the semi-circular RF
tunneling electrode. After tunneling is completed, but prior to
cutting a sphere, the coordinates of the excision specimen are
confirmed, preferably with the assistance of computer aided imaging
and guidance technology. The semi-circular rotational electrode
blade of the RF loop is then activated and used to cut the sphere,
and is rotated by the drive electrical cables attached to the power
drive. Simultaneously, the tissue is immobilized and any blood is
aspirated by vacuum. As the RF loop is rotated, it pulls along the
containment sheath or bag that surrounds the spherical specimen.
After the sphere is fully cut, the RF loop is held in place and the
containment sheath is pulled taught around the sphere by a draw
cord to reduce the sphere's volume to aid in its removal. The
device and sphere are then removed from the body
simultaneously.
US Patent Application 20020120265, to Fowler, entitled, "Symmetric
conization electrocautery device," whose disclosure is incorporated
herein by reference, describes a tissue electrocautery device that
accommodates anatomical structures lying at more than one
longitudinal axes. Such a circumstance is encountered when
attempting to perform symmetric tissue electrocautery of an
endocervical canal where the longitudinal axis of the vaginal vault
is at an angle to the longitudinal axis of the endocervical canal.
The device of the present invention uses a hollow housing, elongate
along a first longitudinal axis, having a proximal portion with a
proximal end and a distal end, and includes a distal portion from
the distal end. The distal portion is elongate along a second
longitudinal axis and pivotable in relation to the proximal portion
at a selectable angle to the first longitudinal axis. Within the
housing is a rotatable electrically conducting mechanism, adapted
to conduct electrocautery energy from an electrode proximal to the
housing proximal portion to a coupling proximate the distal
portion, while rotating the coupling with a removable handle
proximal to the housing proximal portion. The electrical energy is
delivered to an electrocautery head, carrying an electrocautery
wire, operably electrically engageable with the coupling and
rotatable around a longitudinal axis parallel the second
longitudinal axis, electrocauterizing tissue of a human patient
while rotating around its longitudinal axis.
In spite of these works, clean removal of malignancies, surrounded
by definite and sufficient clean margins, remains an elusive
goal.
SUMMARY OF THE INVENTION
The present invention provides a hand-held, integrated tool, having
a tissue-type sensor, for determining the tissue type at a near
zone volume of a tissue surface, and a distance-measuring sensor,
for determining the distance to an interface with another tissue
type. The tool is operable for (i) confirming an existence of a
clean margin of healthy tissue around a malignant tumor, which is
being removed, and (ii) determining the width of the clean margin,
wherein both are performed in real time, while the malignant tumor
is being removed. The tissue-type sensor may be selected from the
group of a sensor for tissue electromagnetic properties, a
dielectric sensor, an impedance sensor, a sensor for optical
fluorescence spectroscopy, a sensor for optical reflectance
spectroscopy, an MRI sensor, an RF sensor, an MW sensor, a
temperature sensor, and infrared thermography sensor, or another
tissue-characterization sensor, as known. The distance-measuring
sensor may be an ultrasound transducer, an MRI probe, an invasive
needle with a strain or pressure gauge, or another tissue distance
measuring sensor, as known. The integrated tool may further include
a position tracking device and an incision instrument. The soft
tissue may be held within a fixed frame, while the tumor is being
removed. Additionally a method for malignant tumor removal is
provided, comprising, fixing the soft tissue within a frame,
performing imaging with the hand-held, integrated tool, from a
plurality of locations and orientations around the soft tissue,
reconstructing a three-dimensional image of the soft tissue and the
tumor within, defining a desired clean margin on the reconstructed
image, calculating a recommended incision path, displaying the
recommended path on the reconstructed image, and cutting the tissue
while determining its type, at the near zone volume of the incision
surface, by the hand-held integrated tool. The method may further
include continuously imaging with the cutting, continuously
correcting the reconstructed image and the recommended incision
path, and continuously determining the tissue type, at the near
zone volume of the incision surface.
In accordance with one aspect of the present invention, there is
provided an integrated tool, for clean-margin assessment,
comprising:
a structure, which defines a proximal end with respect to a tissue
and which is adapted for placement proximally to the tissue;
a tissue-type sensor, mounted on the structure, for determining a
tissue type at a near zone volume of a tissue surface; and
a distance-measuring sensor, mounted on the structure, for
determining a distance between the tissue surface and an interface
with another tissue type,
wherein the integrated tool is configured as a hand-held tool.
In accordance with an additional aspect of the present invention,
the another tissue type is a cancerous tissue, and the integrated
tool may be used to assess:
whether the tissue type at the near zone volume of the tissue
surface is healthy; and the distance between the tissue surface and
an interface with the cancerous tissue.
In accordance with an additional aspect of the present invention,
the integrated tool is adapted for operation in tandem with a
surgical tool, for a real-time correction of a clean margin, where
necessary.
In accordance with an additional aspect of the present invention,
the integrated tool includes an incision instrument, integrated
therewith, for a real-time correction of a clean margin, where
necessary.
In accordance with an additional aspect of the present invention,
the incision instrument may be selectively retracted and
selectively deployed.
In accordance with an additional aspect of the present invention,
the incision instrument is a diathermial incision instrument.
In accordance with an additional aspect of the present invention,
the tissue-type sensor is selected from the group consisting of a
sensor for tissue electromagnetic properties, a dielectric sensor,
an impedance sensor, a sensor for optical fluorescence
spectroscopy, a sensor for optical reflectance spectroscopy, an MRI
sensor, an RF sensor, an MW sensor, a temperature sensor, and
infrared thermography sensor.
In accordance with an additional aspect of the present invention,
the tissue-type sensor is a dielectric-property sensor, formed
substantially as a coaxial cable.
In accordance with an additional aspect of the present invention,
the tissue surface is selected from the group consisting of a skin,
a tissue lumen, and an incision surface.
In accordance with an additional aspect of the present invention,
the distance-measuring sensor is an ultrasound transducer.
In accordance with an additional aspect of the present invention,
the distance-measuring sensor is formed of two ultrasound
transducers.
In accordance with an additional aspect of the present invention,
the distance-measuring sensor is formed of an array of ultrasound
transducers, which may be selectively steered.
In accordance with an additional aspect of the present invention,
the distance-measuring sensor is selected from the group consisting
of a strain gauge and a pressure sensor.
In accordance with an additional aspect of the present invention,
the distance-measuring sensor is an MRI probe.
In accordance with an additional aspect of the present invention,
the integrated tool is operative with a guide wire, wherein a
proximal tip of the guide wire, with respect to the tissue, is
placed within the another tissue type.
In accordance with an alternative aspect of the present invention,
the integrated tool is operative with a guide wire, wherein a
proximal tip of the guide wire, with respect to the tissue, is
placed in close proximity with the another tissue type.
In accordance with an additional aspect of the present invention,
the integrated tool is operative with a guide wire, wherein the
distance-measuring sensor is an ultrasound transducer, and the
guide wire further includes a guide wire ultrasound transducer, at
a proximal tip thereof, with respect to the tissue, for emitting
ultrasound signals, indicative of the proximal-tip distance from
the integrated tool.
In accordance with an additional aspect of the present invention,
the integrated tool is operative with a guide wire, wherein the
distance-measuring sensor is an ultrasound transducer, and the
guide wire further includes a guide wire ultrasound transducer, at
a proximal tip thereof, with respect to the tissue, for emitting
ultrasound signals, indicative of the proximal-tip position with
respect to the integrated tool, by triangulation.
In accordance with an additional aspect of the present invention,
the integrated tool includes a position-tracking device.
In accordance with an additional aspect of the present invention,
the position-tracking device is correlated with a coordinate system
of a fixed frame, within which, the tissue is held fixed in
place.
In accordance with another aspect of the present invention, there
is provided a system for clean-margin assessment, comprising:
a hand-held, integrated tool, for clean-margin assessment, which
comprises: a structure, which defines a proximal end with respect
to a tissue and which is adapted for placement proximally to the
tissue; a tissue-type sensor, mounted on the structure, for
determining a tissue type at a near zone volume of a tissue
surface; and a distance-measuring sensor, mounted on the structure,
for determining a distance between the tissue surface and an
interface with another tissue type;
a computerized system, which comprises: a tissue-type-sensor
analyzer, associated with the tissue-type sensor; a
distance-measuring-sensor analyzer, associated with the
distance-measuring sensor; an output device, which provides output
of measurements by the tissue-type sensor and the
distance-measuring sensor.
In accordance with an additional aspect of the present invention,
the system includes a fixed frame for holding the tissue
therein.
In accordance with an additional aspect of the present invention,
the system includes a position-tracking device and a
position-tracking-device analyzer.
In accordance with an additional aspect of the present invention,
the system includes a computer.
In accordance with yet another aspect of the present invention,
there is provided a system for clean-margin assessment,
comprising:
a fixed frame for holding a tissue therein, the frame defining a
coordinate system;
a hand-held, integrated tool, for clean-margin assessment, which
comprises: a structure, which defines a proximal end with respect
to the tissue and which is adapted for placement proximally to the
tissue; a tissue-type sensor, mounted on the structure, for
determining a tissue type at a near zone volume of a tissue
surface; an imager, operative as a distance-measuring sensor,
mounted on the structure, for determining a distance between the
tissue surface and an interface with another tissue type; and a
position-tracking device, mounted on the structure and correlated
with the coordinate system;
a computerized system, which comprises: a
tissue-type-sensor-analyzer, associated with the tissue-type
sensor; a distance-measuring-sensor analyzer, associated with the
distance-measuring sensor; a position-tracking-device analyzer,
associated with the position-tracking device; a computer, for
receiving data from the tissue-type-sensor analyzer, the
distance-measuring-sensor analyzer, and the
position-tracking-device analyzer, and performing analysis thereof;
an output device, associated with the computer.
In accordance with still another aspect of the present invention,
there is provided a method of clean-margin assessment,
comprising:
providing a hand-held, integrated tool, for clean-margin
assessment, which comprises: a structure, which defines a proximal
end with respect to a tissue and which is adapted for placement
proximally to the tissue; a tissue-type sensor, mounted on the
structure, for determining a tissue type at a near zone volume of a
tissue surface; and a distance-measuring sensor, mounted on the
structure, for determining a distance between the tissue surface
and an interface with another tissue type;
determining the tissue type at the near zone volume of the tissue
surface; and
determining the distance between the tissue surface and the
interface with the another tissue type.
In accordance with yet another aspect of the present invention,
there is provided a method of clean-margin assessment,
comprising:
providing a hand-held, integrated tool, for clean-margin
assessment, which comprises: a structure, which defines a proximal
end with respect to a tissue and which is adapted for placement
proximally to the tissue; a tissue-type sensor, mounted on the
structure, for determining a tissue type at a near zone volume of a
tissue surface; and a non-invasive imager, mounted on the
structure; and a position-tracking device, mounted on the
structure;
fixing the tissue within a fixed frame, which defines a coordinate
system;
imaging the tissue, from at least two locations and orientations,
by the hand-held, integrated tool;
reconstructing a three dimensional image of the tissue;
displaying the three dimensional image of the tissue;
defining a desired clean margin around another tissue type;
displaying the desired clean margin;
calculating a recommended incision path;
displaying the recommended incision path;
providing an incision instrument;
cutting along the recommended incision path; and
determining the tissue type at the near zone volume of the tissue
surface, by the hand-held, integrated tool.
In accordance with an additional aspect of the present invention,
the method includes:
continuously imaging the tissue, from different locations and
orientations along the tissue surface, by the hand-held, integrated
tool;
continuously correcting the recommended incision path; and
continuously displaying the continuously corrected recommended
incision path.
In accordance with an additional aspect of the present invention,
the method includes continuously determining the tissue type, at
the near zone volume of the incision surface, by the hand-held,
integrated tool.
Unless otherwise defined, all technical and scientific terms used
herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Although
methods and materials similar or equivalent to those described
herein can be used in the practice or testing of the present
invention, suitable methods and materials are described below. In
case of conflict, the patent specification, including definitions,
will control. In addition, the materials, methods, and examples are
illustrative only and not intended to be limiting.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with
reference to the accompanying drawings. With specific reference now
to the drawings in detail, it is stressed that the particulars
shown are by way of example and for purposes of illustrative
discussion of the preferred embodiments of the present invention
only, and are presented in the cause of providing what is believed
to be the most useful and readily understood description of the
principles and conceptual aspects of the invention. In this regard,
no attempt is made to show structural details of the invention in
more detail than is necessary for a fundamental understanding of
the invention, the description taken with the drawings making
apparent to those skilled in the art how the several forms of the
invention may be embodied in practice.
In the drawings:
FIGS. 1a-1f schematically illustrate the application of an
integrated tool for clean-margin assessment to a soft tissue that
contains a cancerous tissue within and the principles of
clean-margin assessment, in accordance with the present
invention;
FIGS. 2a-2c schematically illustrate an isometric view, a frontal
view, and a cross-sectional view of the integrated tool for
clean-margin assessment, in accordance with the present
invention;
FIG. 3 schematically illustrates an ultrasound distance-measuring
sensor of the integrated tool for clean-margin assessment, in
accordance with the present invention;
FIGS. 4a-4d further illustrate the operational manner of the
integrated tool for clean-margin assessment, in accordance with the
present invention;
FIGS. 5a-5c further illustrate the operational manner of the
integrated tool for clean-margin assessment, in accordance with the
present invention;
FIG. 6 schematically illustrates an overall system for clean-margin
assessment, in accordance with the present invention;
FIGS. 7a-7d schematically illustrate the integrated tool for
clean-margin assessment, which further includes a retractable
knife, in accordance with a preferred embodiment of the present
invention;
FIGS. 8a-8b schematically illustrate the integrated tool for
clean-margin assessment, operative with a frame for fixing a soft
tissue, in accordance with a preferred embodiment of the present
invention;
FIGS. 9a and 9b schematically illustrate the integrated tool for
clean-margin assessment, wherein the tissue-type sensor is formed
as a horn antenna, for RF or MW, in accordance with still another
embodiment of the present invention;
FIGS. 10a and 10b schematically illustrate the integrated tool for
clean-margin assessment, wherein the tissue-type sensor is formed
as an optical sensor, in accordance with yet another embodiment of
the present invention;
FIGS. 11a and 11b schematically illustrate the integrated tool for
clean-margin assessment, wherein the tissue-type sensor is formed
as an MRI sensor, in accordance with yet another embodiment of the
present invention;
FIGS. 12a and 12b schematically illustrate the integrated tool for
clean-margin assessment, wherein the distance-measuring sensor is
formed as a strain gauge, in accordance with still another
embodiment of the present invention;
FIGS. 13a and 13b schematically illustrate the integrated tool for
clean-margin assessment, wherein the distance-measuring sensor is
formed as a pressure sensor, in accordance with still another
embodiment of the present invention; and
FIGS. 14a and 14b illustrate, in flowchart forms, surgical methods
of tumor removal, using the integrated tool for clean-margin
assessment, in accordance with embodiments of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention is of an integrated tool, having a
tissue-type sensor, for determining the tissue type at a near zone
volume of a tissue surface, and a distance-measuring sensor, for
determining the distance to an interface with another tissue type.
The tool is operable for (i) confirming an existence of a clean
margin of healthy tissue around a malignant tumor, which is being
removed, and (ii) determining the width of the clean margin,
wherein both are performed in real time, while the malignant tumor
is being removed. The tissue-type sensor may be selected from the
group of a sensor for tissue electromagnetic properties, a
dielectric sensor, an impedance sensor, a sensor for optical
fluorescence spectroscopy, a sensor for optical reflectance
spectroscopy, an MRI sensor, an RF sensor, an MW sensor, a
temperature sensor, and infrared thermography sensor, or another
tissue-characterization sensor, as known. The distance-measuring
sensor may be an ultrasound transducer, an MRI probe, an invasive
needle with a strain or pressure gauge, or another tissue distance
measuring sensor, as known. The integrated tool may further include
a position tracking device and an incision instrument. The soft
tissue may be held within a fixed frame, while the tumor is being
removed. Additionally a method for malignant tumor removal is
provided, comprising, fixing the soft tissue within a frame,
performing imaging with the hand-held, integrated tool, from a
plurality of locations and orientations around the soft tissue,
reconstructing a three-dimensional image of the soft tissue and the
tumor within, defining a desired clean margin on the reconstructed
image, calculating a recommended incision path, displaying the
recommended path on the reconstructed image, and cutting the tissue
while determining its type, at the near zone volume of the incision
surface, by the hand-held integrated tool. The method may further
include continuously imaging with the cutting, continuously
correcting the reconstructed image and the recommended incision
path, and continuously determining the tissue type, at the near
zone volume of the incision surface.
Before explaining at least one embodiment of the invention in
detail, it should be understood that the invention is not limited
in its application to the details of construction and the
arrangement of the components set forth in the following
description or illustrated in the drawings. The invention is
capable of other embodiments or of being practiced or carried out
in various ways. Also, it is to be understood that the phraseology
and terminology employed herein is for the purpose of description
and should not be regarded as limiting.
Referring now to the drawings, FIGS. 1a-1f schematically illustrate
the principles of clean margin assessment and the application of a
hand-held, integrated tool 10 for clean-margin assessment, in
accordance with the present invention.
The principles of clean margin assessment may be understood using
the examples of FIGS. 1a-1d. These illustrate tissue portions 15
which have been removed from the body. These portions include a
first tissue type of healthy tissue 14, enclosing or partly
enclosing a second tissue type of cancerous or otherwise abnormal
tissue 16. A tissue surface 18, which is generally the incision
surface, bounds each of the tissue portions 15.
However, it will be appreciated that the tissue surface 18 may be a
skin, a body lumen, or an incision surface.
As seen in FIG. 1a, the incision surface 18 has a positive margin
27 at a location 19. This means that cancerous or otherwise
abnormal cells have reached the surface 18 or the near zone volume
of the surface 18, at the location 19. This may happen when the
incision was performed right through the cancerous or abnormal
second tissue type 16. Alternatively, this may happen when the
incision is performed at the interface between the first and second
tissue types, 14 and 16.
The near zone at the tissue surface 18 is at least one cell layer
in thickness, and preferably several cell layers in thickness. In
practice, it may range from about 100 microns to about 500
microns.
Thus, the positive margin 27 may be defined as a situation where
the tissue surface 18, or the near zone at the tissue surface 18,
contains at least one cancerous cell.
FIG. 1a further illustrates a clean margin at a location 17, where
the tissue surface 18, or the near zone at the tissue surface 18,
contains no cancerous cells, and thus has a clean margin 24.
FIG. 1b illustrates another example of the positive margin 27, this
time at the location 17. The positive margin of FIG. 1b, however,
is due to a shoot 29, which stems from the second tissue type 16
and which reaches to the surface 18.
By contrast, FIGS. 1c and 1d illustrate examples of tissue portions
15 that have been excised with clean margins 24, at all
locations.
FIG. 1e illustrates a model for clean margin assessment, showing
the second, cancerous tissue type 16 and a layer of a tissue 13,
surrounding it. The tissue 13 may be a healthy tissue, but may be
partly cancerous or otherwise abnormal. The aim in characterizing
the tissue surface 18 is to determine the type of the tissue 13 at
various locations along the surface 18. Additionally, when the
tissue surface 18 is characterized as the clean margin 24, a depth
25 to an interface 22 with the second tissue type 16, may be
defined. While a sufficient depth may be realized when the depth 25
is only 1 cell layer in thickness, or about 40 microns, it is
generally desired that the depth 25 be between about 0.1 and 10
mm.
It will be appreciated that other dimensions for the depth 25 of
the clean margin may be desired and may depend on the size and type
of the cancerous tumor, forming the second tissue type 16.
During a surgical operation, for the removal of a cancerous tumor,
in a breast for example, it is important to ensure that the
incision is made through a healthy tissue, so that all the
cancerous tissue is completely contained within the healthy tissue
that is being removed. Thus, the indicated need is to remove the
tissue portion 15, such that:
i. the cut is made through the first tissue type 14 of healthy
tissue, so as to completely contain the second tissue type 16
within;
ii. the depth 25 of the clean margin 24 of the first tissue type 14
is sufficient.
In accordance with the present invention, as illustrated by FIG.
1f, this indicated need is fulfilled by the hand-held, integrated
tool 10 for clean-margin assessment, by:
i. a first sensor for characterizing the near zone volume of the
tissue surface 18, to ensure that it is of the first tissue type 14
of healthy tissue; and
ii. a second sensor for measuring the depth 25 of the clean margin
24, to verify that there is sufficient depth between the tissue
surface 18 and the interface 22, which bounds the second tissue
type 16.
It is important to note that either sensor alone would be
insufficient for the task, since it would not give sufficient
information about both the character of the near zone volume of the
tissue surface and the depth of the clean margin. The prior art for
example, includes methods for determining the depth of the margin
but lacks the ability to characterize the tissue of which the
margin is formed, so as to ensure that the margin which is measured
is clean. It is by this aspect, of both characterizing the tissue
of the margin and measuring its depth, that the present invention
overcomes the shortcomings of prior art configurations.
FIG. 1f further illustrates the application of the hand-held,
integrated tool 10 for clean-margin assessment, to a tissue 12. The
tissue 12 includes the healthy tissue, which forms the first tissue
type 14. Additionally, the tissue 12 includes the cancerous or
otherwise abnormal tissue, which forms the second tissue type 16,
enclosed within the first tissue type 14.
In the example of FIG. 1f, the integrated tool 10 determines that a
distance 20 between the tissue surface 18 and the interface 22,
which bounds the second tissue type 16, is about twice as much as
the desired depth 25 of the clean margin 24. In that case, a
surgeon may decide to approach the second tissue type 16 further,
in order to keep the size of the portion for removal minimal.
It will be appreciated that the integrated tool 10 may be further
used to characterize additional tissue types and determine the
distances between their interfaces. The various tissue types may
include bone tissue, fat tissue, muscle tissue, cancerous tissue,
or blood clot tissue.
Referring further to the drawings, FIGS. 2a-2c schematically
illustrate an isometric view, a proximal view, with respect to the
tissue 12, and a cross-sectional view of the integrated tool 10 for
clean-margin assessment, in accordance with a first embodiment of
the present invention.
The integrated tool 10 has a proximal end 30 and a distal end 32,
with respect to the surface 18 (FIG. 1). In accordance with the
preferred embodiment of the present invention, a tissue-type sensor
33 determines the characteristics of the tissue in the near zone
volume of the surface 18, for example, whether fat, muscle, bone,
healthy, cancerous, or otherwise abnormal. Additionally, a
distance-measuring sensor 38 measures the distance 20 from the
surface 18 to the interface 22 with the second tissue type 16.
In accordance with the first embodiment of the present invention,
the tissue-type sensor 33 measures the electrical properties of the
tissue type 13. By comparing the results with known tissue
properties, the characteristic of the tissue type 13 is
determined.
For example, the tissue-type sensor 33 may be constructed as a
coaxial cable 44, having an inner electrode 34 and an outer
electrode 36, which together form the sensor 33. The outer
electrode 36 may be grounded.
Further in accordance with the first embodiment of the present
invention, the distance-measuring sensor 38 is at least one
ultrasound transducer 38.
Preferably, the coaxial cable 44 is located within an overall
structure 45. The distance-measuring sensor 38, such as the at
least one ultrasound transducer 38 is also mounted on the structure
45, for example, along side the tissue-type sensor 33.
Additionally, the distance-measuring sensor 38 may be formed of at
least two ultrasound transducers 38, one operating as a transmitter
and the other as a receiver. The advantage there is that the
instrumentation dead time is shorter.
Furthermore, the distance-measuring sensor 38 may be formed as an
array of ultrasound transducers 38, for providing steering and
focusing capabilities, as known.
Signals from the tissue-type sensor 33 and the distance-measuring
sensor 38 are transferred for analysis through a cable 46 to a
computerized system 95, described hereinbelow in conjunction with
FIG. 6.
Preferably, the inner electrode 34 has a diameter 40 of between
about 0.2 and 1.5 mm, and the outer electrode 36 has an inner
diameter 42 of between about 3.0 and 10.0 mm, and is about 0.5 mm
thick. Additionally, the outer electrode 36 is covered is with an
insulating sheath 49 made of an insulating material, for example,
Teflon. It will be appreciated that other dimensions, which may be
larger or smaller, may similarly be used. The sensors 38 and 33 may
be encased in a filler material 39, for example epoxy, which may be
formed as a plug that fits into the structure 45, for example, as
shown in FIG. 2c.
Preferably, the ultrasound transducer 38 operates at a frequency
range of between about 0.5 MHz and about 40 MHz. It has an accuracy
of about 3 mm, when operating at the lower range of 0.5 MHz, and an
accuracy of about 40 micron, when operating at the higher range of
40 MHz.
The integrated tool 10 may further include a position-tracking
device 50, for example, the miniBIRD.RTM. 500 or the miniBIRD.RTM.
800, which are miniaturized magnetic tracking systems having six
degrees of freedom and using sensors, which are merely 5 mm wide,
produced by Ascension Technology Corporation, P.O. Box 527
Burlington, Vt. 05402, USA. They are described in
http://www.ascension-tech.com/products/minibird.php, downloaded on
Mar. 15, 2005. The position-tracking device 50 may provide the
coordinates of the ultrasound measurements, thus enabling a
three-dimensional image reconstruction of the ultrasound.
Referring further to the drawings, FIG. 3 schematically illustrates
the ultrasound distance-measuring sensor 38 of the integrated tool
10, in operation, in accordance with the present invention.
For operation, the proximal end 30 of the integrated tool 10 is
brought proximally to the tissue surface 18, of the tissue 12, so
as to make contact or near contact with it. The tissue 12 includes
the first tissue type 14 of healthy tissue, preferably at the outer
portion thereof, and the second tissue type 16 of abnormal tissue,
enclosed by the first tissue type 14 of healthy tissue, with tissue
13, which is suspicious as possibly containing cancerous or
otherwise abnormal tissue, surrounding the second tissue type 16.
Preferably, tissue 16 is bounded by the interface 22.
Preferably, at least two ultrasound transducers 38 are used, 38A
and 38B, wherein the transducer 38A is a transmitter for
transmitting an ultrasound wave 58, and the transducer 38B is the
receiver, for receiving an ultrasound echo 60, from the interface
22 within the tissue 12. In this manner, instrumentation dead time
is reduced.
Preferably, the ultrasound sensor 38 is preset for a focal distance
of about 5 mm, which is the desired depth 25 of the clean margin
24, thus providing the most accurate results for this distance.
FIG. 3 further illustrates the structure 45 of the coaxial cable 44
and the tissue-type sensor 33. Additionally, the position-tracking
device 50 is shown. When correlated with a tissue coordinate system
54, illustrated hereinbelow, in conjunction with FIG. 6, it may be
used together with the ultrasound sensor 38, to provide a
three-dimensional image of the tissue 12 and the abnormal tissue
type 16 within.
The cable 46 carries the measurements to the computerized system
95, described hereinbelow in conjunction with FIG. 6.
Referring further to the drawings, FIGS. 4a-4d further illustrate
the operational manner of the integrated tool 10 for clean-margin
assessment, in accordance with the present invention.
Generally, to localize the tumor within the breast, a radiologist
may place a guide wire under x-ray or ultrasound guidance, so that
the proximal tip of the guide wire, with respect to the tissue, is
in the tumor. Alternatively, an imaging modality alone, for
example, mammography, CT, ultrasound, or another imaging modality
may be used to locate the tumor. The patient is then transported to
the operating room, where the surgeon uses the guide wire, or the
image, or palpation to locate the tumor in the breast and to excise
a portion of tissue including the cancerous portion and a layer of
healthy tissue surrounding the cancerous portion. The process of
inserting a guide wire is termed, pre-procedure.
In accordance with the present invention, two methods are possible,
without pre-procedure, as illustrated in FIGS. 4a-4c, and with
pre-procedure, as illustrated in FIG. 4d.
Thus, FIGS. 4a-4c schematically illustrate the use of the
integrated tool 10 when no guide wire is used.
As seen in FIG. 4a, the integrated tool 10 may be used on the
tissue surface 18, during the removal of the portion 15, to verify
that the cutting proceeds as planned. At this stage, the near zone
volume of the surface 18 should detected by the tissue type sensor
33 to be of the first tissue type 14 of healthy tissue, and the
interface 22 with the second tissue type 16 should be detected at
the desired depth 25. Corrections can be made in real time.
As seen in FIG. 4b, the integrated tool 10 may be used on the
tissue surface 18, after the removal of the portion 15, to verify
that the all the cancerous tissue has been eliminated. At this
stage, the near zone volume of the surface 18 should detected by
the tissue type sensor 33 to be of the first tissue type 14 of
healthy tissue, and no interface 22 and no second tissue type 16
should be detected. As seen in FIG. 4b, where a portion 72 of the
second tissue type 16 remained, the integrated tool 10 will
identify it both by the character of the near zone volume of the
tissue surface 18 around the portion 72, and by the presence of the
interface 22, in back of the second tissue type 16, indicating that
two types of tissue remained.
As seen in FIG. 4c, the integrated tool 10 may be used on the
tissue surface 18, of the removed portion 15, after removal. This,
to verify that the all the cancerous tissue is surrounded by the
clean margin 24 of the first tissue type 14 of healthy tissue, and
of sufficient depth 25. At this stage, the near zone volume of the
surface 18 should be of the first tissue type 14, and the interface
22 should be detected at the desired depth 25.
Additionally, as seen in FIG. 4c, where there is no clean margin,
as shown by a surface 74, the integrated tool 10 will identify it
both by the character of the near zone volume of the tissue surface
18 at the surface 74, and by the absence of the interface 22,
around the desired depth 25.
FIG. 4d schematically illustrates the use of the integrated tool 10
with a guide wire 78 that has been inserted during pre-procedure,
with the help of x-ray or another imaging modality. This procedure
often applies to non-palpable tumors, which are difficult to
detect.
Preferably, the distance-measuring sensor 38 is an ultrasound
transducer, and the guide wire 78 is visible by the ultrasound.
Additionally, a guide-wire transducer 82 may be mounted on the tip
80, for sending signals that may be received by the
distance-measuring sensor 38. Thus, the distance-measuring sensor
38 may estimate the distance to the tip 80, hence the distance to
the second tissue type 16.
The guide wire transducer 82 may be, for example, a
micro-electromechanical system (MEMS) ultrasound transducer, with a
typical size of about 100 .mu.m in diameter. Furthermore, the
distance-measuring sensor 38 may include three transducers, for
calculating the exact position of the guide wire transducer 82, by
triangulation. It will be appreciated that in the calculation of
the distance between the guide wire transducer 82 and the
distance-measuring sensor 38, it is assumed that the sound velocity
in cancerous tissue and in healthy tissue is about the same.
Alternatively, the sensor 82 at the tip 80 of the guide wire 78 may
be a magnetic positioning device, coupled with an RF transmitter,
for transmitting its position, via RF signals, which may be
received by an RF receiver on the integrated tool 10.
When the portion 15 has been removed, FIGS. 4b and 4c apply, as
before.
Referring further to the drawings, FIGS. 5a-5c further illustrate
the operational manner of the integrated tool 10 for clean-margin
assessment, in accordance with the present invention.
As seen in FIG. 5a, as a first step, the integrated tool 10 is
applied to an external surface 11, such as a skin, forming the
surface 18, prior to cutting and prior to the removal of the
portion 15 (FIG. 1). Alternatively, the surface 18 may be a lumen.
The tissue-type sensor 33 will probably detect that the surface 18
is of the first tissue type 14 of healthy tissue, and the
distance-measuring sensor 38 will detect the interface 22 with the
second tissue type 16 at some depth.
As seen in FIG. 5b, when the incision begins, for the removal of
the portion 15 (FIG. 1), the integrated tool 10 is applied to the
tissue surface 18, now the tissue surface 18, to verify that the
cutting proceeds as planned. At this stage, the tissue-type sensor
33 will detect that the near zone volume of the tissue surface 18
is of the first tissue type 14 of healthy tissue, and the
distance-measuring sensor 38 will detect the interface 22 with the
second tissue type 16 at some depth, approaching the desired depth
25 of the clean margin 24. Corrections and adjustments can be made
in real time.
As seen in FIG. 5c, if cutting went too far, the tissue-type sensor
33 will detect that the near zone volume of the tissue surface 18
is of the second tissue type 16 of abnormal tissue, and the
distance-measuring sensor 38 will not be able to provide useful
information, as no clean margin exists.
Referring further to the drawings, FIG. 6 schematically illustrates
an overall computerized system 95, for clean-margin assessment, in
accordance with the present invention.
System 95 includes the integrated tool 10, having the structure 45,
on which the tissue-type sensor 33 and the distance-measuring
sensor 38 are mounted. Preferably, both sensors are located at the
proximal end 30, with respect to the tissue. Additionally, the
integrated tool 10 may include the position-tracking device 50, for
providing its coordinates with respect to the frame of reference
54, which defines a six-degree coordinate system, of x, y, z, and
the rotational angles around them, .omega., .theta., and .rho..
Data from the integrated tool 10 is carried to appropriate
analyzers, preferably associated with a computer 90 for analysis.
It will be appreciated that the computer 90 may be a personal
computer, a laptop, a palmtop, a microcomputer, or another
computer, as known.
For example, where the tissue-type sensor 33 is an electrical
properties sensor, constructed essentially as the coaxial cable 44
(FIGS. 2a-2c), an electrical properties sensing module 94 includes,
for example, an impedance analyzing external unit, such as Agilent
4396A, and a test fixture 89 connected via a coaxial cable to the
impedance analyzing external unit.
Similarly, the distance-measuring sensor 38, such as the ultrasound
transducer 38 is associated with an ultrasound signal generator and
analyzer 96. The position-tracking device 50 may be associated with
an analyzer 98. The sensors may be battery operated or associated
with power supply units.
The computer 90 which receives the data from the analyzers,
preferably includes a user interface, for example, a keyboard 97,
or knobs, and may further include storage systems, such as a read
and write drive 91, a USB port 93, and a display screen 92.
It will be appreciated that where a different tissue-type sensor 33
is used, the unit 94 type will complement that sensor 33. For
example, where sensor 33 is an lo optical sensor, the unit 94 will
be an optical analyzer. Similarly, where a different distance
measuring sensor 38 is used, the unit 96 will complement that
sensor 38.
Information from the distance-measuring sensor 38 together with
that of the position-tracking device 50 may be used for
reconstructing a three-dimensional image of the tissue, by the
computer 90. Additionally, the three-dimensional image may be is
displayed on the screen 92.
The system 95 may further include a guide wire 78. At the proximal
end 80, the guide wire may include a sensor 82, which may be an
ultrasound transducer or a magnetic positioning device, coupled
with a transmitter, for transmitting the positioning of the
proximal tip, when inserted in the tissue, as taught hereinabove,
in conjunction with FIG. 4d. Preferably, the sensor 82 is wireless,
and operates via external interrogation, for example, from the
distance-measuring sensor 38, or on battery.
Referring further to the drawings, FIGS. 7a-7d schematically
illustrate the integrated tool 10, which further includes a
retractable knife 106, in accordance with a preferred embodiment of
the present invention.
As seen in FIG. 7a, the knife is retracted, and the tool is used as
described hereinabove.
As seen in FIG. 7b, the knife is deployed, and the tool is used for
removing the portion 15.
Thus the surgeon may use the integrated tool 10 both for measuring
and characterizing the clean margin and for removing the portion
15.
FIG. 7c illustrates the proximal view of the integrated tool 10, in
accordance with the present embodiment, while FIG. 7d provides a
cross-sectional view.
Retraction and deployment are controlled by a knob 108.
The knife 106 may be a cold knife, a diathermal knife, or another
knife, as known.
Referring further to the drawings, FIGS. 8a-8b schematically
illustrate the integrated tool 10, operative with a frame 100 for
fixing the soft tissue 12, in accordance with a preferred
embodiment of the present invention.
The frame 100 has a support plate 101 and a compression plate 102.
The compression plate 102 defines an opening 104, through which the
integrated tool 10 may be inserted.
In accordance with the present invention various sensors may be
used for the tissue-type sensor 33, for characterizing the near
zone volume of the tissue surface 18 in contact with the integrated
tool 10. These are illustrated below, in conjunction with FIGS.
9a-12b.
Referring further to the drawings, FIGS. 9a and 9b schematically
illustrate the integrated tool 10, wherein the tissue-type sensor
33 is formed as an RF or MW horn antenna 37, mounted on the
structure 45, in accordance with still another embodiment of the
present invention.
The RF or MW horn antenna 37 is associated with an RF/MW
transmission line or wave guide 31, while unit 94 (FIG. 6) is an
RF/MW generation, collection and analysis unit.
The present embodiment relies on RF microwave characterization by
the generation of propagating radiation in the RF microwave region
of the electromagnetic spectrum, towards the tissue, and measuring
its reflection. The radiation is usually transmitted and received
by an antenna, for example the horn antenna 37. The tissue
characterization is done by analyzing the amplitude and phase
difference between the original waves to the reflected wave.
Referring further to the drawings, FIGS. 10a and 10b schematically
illustrate the integrated tool 10, wherein the tissue-type sensor
33 is formed as an optical sensor 47, mounted on the structure 45,
in accordance with yet another embodiment of the present
invention.
An optical signal is generated in an external unit, such as unit 94
(FIG. 6) and transmitted via an optical fiber 41 to the tissue. The
reflection of the light is then received in a dedicated module
inside the optical unit. The optical energy is usually transmitted
to and from the tissue via a lens 43.
The details of optical signal generation, receiving and analyzing
depend on the specific optical method that is chosen. For example,
for reflection spectroscopy, tissue characterization relies on
measuring the relative amplitude and phase of the reflected light
versus the generated light. An example for the reflection
spectroscopy method is described in commonly owned U.S. patent
application Ser. No. 10/298196, whose disclosure is incorporated
herein by reference. It will be appreciated that other methods may
be used, as known.
Alternatively, auto florescence may be used, for measuring emitted
radiation, from the tissue, at different a wavelength than that
originally transmitted. The emitted radiation occurs in response to
excitation by impinging radiation, and may be used for tissue
characterization, for example, as used by Xillix Technologies
Corp., #100-13775 Commerce Parkway, Richmond, British Columbia,
Canada V6V 2V4, Telephone: 604-278-5000, and described in
http://www.xillix.com/index home.cfm. It will be appreciated that
other methods may be used, as known.
Referring further to the drawings, FIGS. 11a and 11b schematically
illustrate the integrated tool for clean-margin assessment, wherein
the tissue-type sensor 33 is formed as an MRI sensor 51, in
accordance with yet another embodiment of the present
invention.
The MRI sensor 51 has a permanent magnet 55, enclosed in an RF coil
53, for example, as taught in commonly owned U.S. Patent
Application 2005/0021019 to Hashimshony et al., entitled "Method
and apparatus for examining substance, particularly tissue, to
characterize its type," whose disclosure is incorporated herein by
reference, and in U.S. Pat. No. 5,572,132, to Pulyer, et al.,
entitled, "MRI probe for external imaging," whose disclosure is
incorporated herein by reference.
In accordance with the present invention various sensors may be
used for the distance-measuring sensor 38, as illustrated below, in
conjunction with FIG. 13.
It will be appreciated that many other tissue characterization
sensors may be used, as known. These may include a sensor for
tissue electromagnetic properties, a dielectric sensor, an
impedance sensor, a sensor for optical fluorescence spectroscopy, a
sensor for optical reflectance spectroscopy, an MRI sensor, a
temperature sensor, and infrared thermography sensor, or another
tissue-characterization sensor, as known.
Referring further to the drawings, FIGS. 12a and 12b schematically
illustrate the integrated tool 10, wherein the distance-measuring
sensor 38 is formed as a strain gauge 66, in accordance with still
another embodiment of the present invention.
The present embodiment utilizes the approach of U.S. Pat. No.
6,546,787 to Schiller et al., whose disclosure is incorporated
herein by reference, and which provides an apparatus and method for
detecting a distance from a tissue edge to a malignant tissue,
enclosed therein, i.e., a margin. The apparatus comprises a needle
having a strain gage, mounted on one of the needles walls. Strain
signals are collected as the needle is moved through the tissue.
The needle is inserted at different points to allow data collection
from different points within the tissue. The data is sent together
with its spatial coordinates to a computerized system, which
provides an image of the structure of the examined tissue.
As seen in FIGS. 12a and 12b, the structure 45 of the integrated
tool 10 may include a lumen 65, wherein a needle 60 may be
retracted and deployed, via a knob 62. The needle has a sharp edge
64, for penetrating the tissue. The strain gauge 66 senses the
tissue resistance to the penetration, and provides data of
resistance as a function of needle penetration depth. These
measurements may be performed at various locations along the tissue
surface 18.
Referring further to the drawings, FIGS. 13a and 13b schematically
illustrate the integrated tool 10, wherein the distance-measuring
sensor 38 is formed as a pressure sensor 68, at the needle's tip,
in accordance with yet another embodiment of the present
invention.
Again, the structure 45 of the integrated tool 10 may include the
lumen 65, wherein the needle 60 may be retracted and deployed, via
the knob 62. The pressure sensor 68 senses the tissue resistance to
the penetration, and provides data of resistance as a function of
needle penetration depth. These measurements may be performed at
various locations along the tissue surface 18.
It will be appreciated that a non-invasive imager may be used for
the distance-measuring sensor 38, for example, an MRI sensor.
Accordingly, the integrated tool 10 may be formed, for example,
with the tissue-type sensor 33 being an optical sensor, and the
distance-measuring sensor 38 being a on-invasive imager, such as an
MRI sensor.
Referring further to the drawings, FIGS. 14a and 14b illustrate, in
flowchart forms, surgical methods of tumor removal, using the
integrated tool 10, in accordance with embodiments of the present
invention,
As illustrated in FIG. 14a, a method 200 provides a computer-guided
surgery, as follows: in a box 202: providing the hand-held,
integrated tool 10, which includes: i. the tissue-type sensor 33,
for determining a tissue type at a near zone volume of a tissue
surface; ii. the non-invasive imager 38, for example, an ultrasound
sensor, or an MRI sensor; and iii. the position tracking device 50.
in a box 204: fixing the tissue within a fixed frame, which defines
a coordinate system, preferably of six-degrees, x, y, z, and the
rotational angles around them, .omega., .theta., and .rho.. in a
box 206: imaging the tissue, within the fixed frame, from at least
two, and preferably, a plurality of locations and orientations, by
the hand-held, integrated tool 10. in a box 208: reconstructing, by
a computer, a three dimensional image of the tissue. in a box 210:
displaying the three dimensional image of the tissue. in a box 212:
defining a desired clean margin around a second tissue type. in a
box 214: displaying the desired clean margin. in a box 216:
calculating a recommended incision path. in a box 218: displaying
the recommended incision path. in a box 220: providing an incision
instrument. in a box 222: cutting along the recommended incision
path. in a box 224: determining the tissue type at the near zone
volume of the tissue surface, by the hand-held, integrated tool
10.
As illustrated in FIG. 14b, a method 230 further provides
continuous correction to the method 200, as follows: in a box 232:
continuously imaging the tissue, from different locations and
orientations along the tissue surface, by the hand-held, integrated
tool 10. in a box 234: continuously correcting the three
dimensional image reconstruction of the tissue, as the tissue is
being cut. in a box 236: continuously correcting the display of the
three dimensional image of the tissue. in a box 238: continuously
correcting the desired clean margin around the second tissue type.
in a box 240: continuously displaying the continuously corrected
desired clean margin. in a box 242: continuously correcting the
recommended incision path. in a box 244: continuously displaying
the continuously corrected recommended incision path. in a box 246
continuously determining the tissue type, at the near zone volume
of the incision surface, by the hand-held, integrated tool 10.
Preferably, the knife is integrated with the tool, as taught in
conjunction with FIGS. 7a-7d.
It is appreciated that certain features of the invention, which
are, for clarity, described in the context of separate embodiments,
may also be provided in combination in a single embodiment.
Conversely, various features of the invention, which are, for
brevity, described in the context of a single embodiment, may also
be provided separately or in any suitable subcombination.
Although the invention has been described in conjunction with
specific embodiments thereof, it is evident that many alternatives,
modifications and variations will be apparent to those skilled in
the art. Accordingly, it is intended to embrace all such
alternatives, modifications and variations that fall within the
spirit and broad scope of the appended claims. All publications,
patents and patent applications mentioned in this specification are
herein incorporated in their entirety by reference into the
specification, to the same extent as if each individual
publication, patent or patent application was specifically and
individually indicated to be incorporated herein by reference. In
addition, citation or identification of any reference in this
application shall not be construed as an admission that such
reference is available as prior art to the present invention.
* * * * *
References